Do I have an exhaust leak around the header flanges?

Question: I suspected an exhaust leak around the header flanges on my Hayabusa, so I had the gaskets replaced at a dealership. However, the sound is still there. They told me it's normal with aftermarket exhausts—is that true?

Answer: No, it is NOT common for Brock’s Performance exhaust systems to leak, and you should never have to “live with” the sound of a leaking exhaust. Our systems are engineered for precise fitment and proper sealing when installed correctly.

In many cases like this, the actual problem isn't the gaskets—it’s the installation.

Common Cause: Overtightening the Header Flange Bolts

Overtightening the bolts at the header flanges can warp or bow the mounting flanges, preventing a proper seal even with new gaskets. Once the flanges are distorted, replacing the gaskets alone will not resolve the leak.

Recommended Solution

• Carefully inspect the header flange surfaces for warping or uneven contact.

• Refer to our installation instructions here to ensure proper torque specs and procedure are followed.

• If necessary, replacement flange kits and Permatex Ultra Copper RTV sealant are available directly from Brock’s Performance to help ensure a proper seal.

If you’re still unsure, feel free to contact our tech support with photos—we're happy to help confirm proper fitment and walk you through troubleshooting.

Stainless Flange Overtightened Example